Cleaning solar panels depends on dirt accumulation, which can hinder energy production. It's possible to clean them yourself considering safety precautions, or have a professional do it.
Check the panel manual to adhere to warranty guidelines. Use water or mild soap, avoiding harsh chemicals. Typically, panels on a 22° pitched roof need cleaning every few years, while flat panels require more frequent cleaning.
Environmental conditions, like dust, tree proximity, or coastal salt mist, can necessitate a regular cleaning schedule. Monitoring system performance can indicate cleaning needs.
How often should you clean your solar panels?
Solar panels are generally self-cleaning to an extent. This applies especially if they are installed at an angle as precipitation like rain can wash away most of the dirt and debris. However, it’s still crucial to ensure that they are clean and working at optimum efficiency. This is because any dirt or bird droppings can obstruct sunlight and reduce power production.
Understanding the importance of clean solar panels
Having clean solar panels is not just about keeping them looking good. The efficiency of your solar panels directly correlates to how clean they are. Panels covered in dirt, dust, bird droppings, or other debris can’t effectively absorb sunlight. Over time as more and more grime and debris collects, output can be severely reduced.
Over time, this lower efficiency can add up to noticeable increases in your energy bills. It’s a simple task, but cleaning your solar panels can save you money. It will also allow a closer inspection of the system and therefore ensure your solar system lasts as long as possible.
Evaluating the dirt accumulation
It is wise to do a visual inspection of your solar panels now and then, if possible and safe. If they look fairly clean and your energy production numbers are within the expected range, a thorough cleaning may not be necessary. However, if they look dirty or you’ve noticed a drop in your PV system’s energy production, it’s probably time for a cleaning.
It is possible to clean solar panels yourself, or you can organise this with your solar installer for the panels to be cleaned along with regular system inspections and check-ups.
Whether you can wash the panels yourself is dependent on your capacity to handle heights safely. You need to consider your safety and take precautions to protect your safety doing this. You should be able to secure yourself with a harness or other measures to protect yourself from falling. So really if it’s not a flat one-storey roof – the question is – is it worth the risk? Maybe it’s better to give the job to a professional.
We recommend consulting the manual for your panels to check the maintenance requirements for the panels. That way you can be sure of the panel manufacturers’ requirements and guidelines. This may also ensure you do not breach the warranty guidelines and void the panel warranty, maybe via the wrong method.
Before attempting to clean the solar panels, you should first switch off the solar system at the inverter and rooftop isolators if present, to reduce the risk of electrocution. It would also be recommended to clean them either early in the morning or late in the afternoon when the sun is low. In that timeframe, the panels produce minimal power and this reduces the risks of electric shock and electrocution.
What to use
If you are washing the panels, then this should be done with water or a very mild soapy solution using a soft cloth, sponge or similar. Do not use harsh chemical cleaners, hard brushes or pressure washers, as these can damage the panels.
Expert cleaning services
Consider hiring professionals if you’re unsure about doing it yourself. The same advice applies if your solar panel setup is in a hard-to-reach or dangerous area. Professionals have the right tools and knowledge to clean solar panels safely without causing any damage.
How often should you clean your panels?
How often the panels need to be cleaned depends on how dirty the panels get. A good guide is that if you see signs of dirt and grime on the panels, then it would be worthwhile cleaning them.
Where panels are tilted on a standard 22⁰ pitched roof, rainwater should be enough to wash off any dust or dirt so that cleaning requirements would be minimal and only need to be done every couple of years.
Where panels are installed at a lower pitch or flat on the roof, the ability of the rain to clean the solar panels is reduced, and the more regularly the panels are likely to require cleaning. We recommend in such situations at least once a year.
Monitoring your system’s performance
Regular monitoring of your solar system’s performance can also provide insights into when cleaning might be necessary. If you notice a significant drop in power generation, it might be a sign that your panels need cleaning.
Cleaning requirements can also depend on environmental conditions. In areas where there are high levels of dust or dirt or areas where there are trees close by, the panels may see the panels getting dirtier quicker and therefore require a more regular cleaning schedule.
Similarly, in coastal areas where there could be salt mist on the panels, it would be recommended to maintain a regular solar panel cleaning schedule. If you are looking to learn more about solar panel maintenance and cleaning, refer to the Clean Energy Regulator here.